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PROFESSIONAL OBSERVATION FORM
 Start Date: 12.11.18 Name: Lundy, Davis, Vandenbos Operation: SAC
 Drainage/Route:  Smiley Creek - Upper Vienna weather station Observed Terrain:  most aspects, 7200-9600' Zone/Region:  Smoky & Boulder Mountains
WEATHER OBSERVATIONS
 HN24: HST: Sky: OVC Precip: Temps:
 Ridgeline Wind: Moderate from the W
 Blowing Snow: None Snow Available for Transport: Small amounts
 Comments: SCT clouds this morning, increasing during the day with approaching system
AVALANCHE OBSERVATIONS
None Reported
SNOWPACK OBSERVATIONS
 HS: 40-60cm, greatest depth on upper elevation shaded/sheltered aspects 
 Upper Pack: 30-40cm FC, still 1F at base of Thanksgiving snow at upper elevations. Steep, upper elevation solar slopes had a thin MFcr at surface. 
 Middle Pack:  
 Lower Pack: Upper elevation, shady aspects have 10-15cm of F- depth hoar to 5mm. 
AVALANCHE PROBLEM ASSESSMENT
Avalanche Characteristics
Character/Avalanche Problem:
Persistent Slab

Layer/Depth:
20181122

Likelihood of Triggering
Sensitivity:
Stubborn

Spatial Distribution:
Specific
Terrain
  Primary Concern Comments: Slab is weakening overall, but still 1F at base and still producing collapses.
STABILITY TESTS
 Stability Test Results:
OBVIOUS SIGNS OF INSTABILITY
 Marked with checkmark if observed:
 Cracking (isolated) Depth: 30-40cm Length: up to 25m
 Collapsing (widespread) Depth: 30-40cm Length: up to 25m
 Comments: Widespread small collapses as we traveled, generally on the order of 5-10m spatially but some were larger.
SNOW STABILITY
 Snow Stability Rating for your observed area: Confidence: Trend:
BOTTOM LINE
 Comments: Mostly a mission to work on Upper Vienna weather station, so no formal snowpack observations. However, the conditions here were similar to the deeper areas on Galena (Titus Ridge for example). I think 6-8" of new snow combined with wind tonight would produce some natural avalanche activity and human-triggerable conditions, more than that would be very exciting.
FILE ATTACHMENTS

IMG_1695.jpg
Collapsing remains widespread

P1110895.JPG